Yes, antibodies can help destroy infected cells.
How Antibodies Target Infected Cells
Antibodies, primarily known for their role in neutralizing pathogens, also play a critical role in eliminating virus-infected cells. Here's how they do it:
-
Recognition: Antibodies recognize virus-specific antigens present on the surface of infected cells. This recognition is a crucial first step in targeting these cells for destruction.
-
Complement Activation: Once an antibody binds to the antigen on an infected cell, it can activate the complement system, a part of the immune system. This activation can occur via both the classic and alternative pathways:
- Classic Pathway: Initiated directly by antibody binding to the cell surface.
- Alternative Pathway: Activated through other mechanisms but can be amplified by antibody presence.
-
Cell Lysis: The activated complement system results in the formation of a membrane attack complex (MAC) that creates pores in the infected cell's membrane. This leads to cell lysis, effectively destroying the infected cell.
Process Description Antibody Recognition Antibodies bind to viral antigens on the surface of infected cells. Complement Activation Antibody binding triggers either the classic or alternative complement pathways. Membrane Attack Complex Activation results in a membrane attack complex on the infected cell. Cell Lysis The membrane attack complex causes pores in the cell membrane, ultimately destroying the infected cell.
Example: Destroying a Virus-Infected Cell
Imagine a cell infected by a virus. Viral proteins (antigens) begin to appear on the cell’s surface. Antibodies specific to these viral antigens circulate in the bloodstream.
- Antibody Binding: When an antibody recognizes and binds to these surface antigens.
- Activation of Complement: This binding initiates the complement cascade.
- Cell Destruction: The result is cell lysis, preventing further viral replication and spread.
In summary, antibodies, by binding to infected cells and activating the complement system, can directly lead to the destruction of those infected cells through lysis.
